Physiologie. (il 



zur Stickstoffnahrung geeignet, wie salicyl-, mellith-, gallus- 

 und chinasaures Ammon ; die letzteren zwei, besonders das 

 Salz der Chinasäure, geben selbst ohne Zuckerzusatz eine gute 

 Pilznahrung, p-oxybenzoesaures Ammon gab sogar ohne Zucker 

 eine höhere Ernte als mit solchem. Der Benzolring kann leicht 

 gesprengt werden, wie z. B. bei der Chinasäure; vermuthlich 

 besteht eine physiologische Verwandtschaft mit den Hexosen 

 (Quercit, Inosit). Auch der Pyridinring kann gesprengt werden, 

 was aus der Verwendbarkeit des nikotinsauren Natrons hervor- 

 geht, während Pyridin selbst aus anderweitigen Ursachen un- 

 geeignet ist; ähnliches dürfte vom Pyrrolring gelten, der im 

 Isatin dem Aspergillus nicht zugänglich ist. Cyan- und Sulfo- 

 cyanverbindungen sind als Stickstoffquelle unbrauchbar, doch 

 verdient die freilich schwache Nährwirkung des Rhodannatriums 

 Beachtung. 



Den Schluss bilden Untersuchungen über den Werth ver- 

 schiedener Kohlenstoffquellen bei gleicher Stickstoffnahrung 

 (Asparagin); hier tritt die Eignung der Hexosen und ihrer 

 Derivate ganz besonders deutlich hervor. 



Hugo Fischer (Bonn). 



LOEW, 0., C a t a 1 a s e , a new Enzyme o f General Occu- 

 rence. (U. S. Dept. of Agric. Report 86. 1901. p. 1—47.) 



Describes an enzyme-catalase-which is able to break up 

 H2 O2. This property not due to any known enzyme hence 

 proposes the above name. Two kinds: insoluble A catalase 

 and soluble B catalase. The former propably a Compound of 

 the soluble form with a nucleo-proteid ; the latter is an albumose 

 and can be liberated by the action of verv dilute alkaline 

 media on the insoluble catalase. The behavior of catalase with 

 a great number of substances is given. The distribution of the 

 enzyme among both highly and lowly organized plants is 

 general, in fact apparently universal, and it is also of wide 

 occurence in the animal kingdom. Says that while catalase 

 does not give the blue reaction with guaiac Solutions or answer 

 to some of the other tests for oxidizing enzymes it is never- 

 theless of this class as is shown by its action on hydroquinone. 



Regarding the function of catalase concludes that since it 

 appears to be present in every cell must have some general 

 purpose. Discusses the possibility of the formation of hydrogen 

 peroxide by respiration processes and the action of catalast 

 in removing this as fast as formed. More catalase is found in 

 anaerobic forms in which there is no normal respiration, con- 

 cludes that the enzyme must act differently. In this connection 

 says as follows: „Catalase must then have still another function, 

 and the writer is inclined to assume for it the faculty also of 

 loosening chemical affinities in certain Compounds to such a 

 degree that the protoplasm itself can more easily split them. 

 or, when oxygen has acces, can more easily oxidize them". 



